In 1926, Samual Amster of Richmond, Kentucky described the extraction of a “wax like substance” from tobacco using a hot water process and then subjecting the resulting liquor to an evaporative step. Despite this extraction, Amster teaches that the (extracted) tobacco “may still be employed for smoking and chewing tobacco.” Amster teaches the use of the tobacco “wax like substance” in candles, shoe polishes and varnish (U.S. Pat. No. 1,624,155).
In 1936, James Garner of Mount Lebanon, Pa., described a method to de-nicotinize tobacco, whereby ammonia treated tobacco is subjected to a butane-solvent based extraction method. When the butane is evaporated, “there is left a mass of nicotine and tobacco wax which together may amount to as much as 6-8% by weight of the tobacco used . . . . Tobacco wax or resin is dark brown in color, burns with the production of acrid fumes, and has a strong odor resembling that of an “old” pipe.” The tobacco wax may be used as an insecticide or may be “returned to the residual tobacco leaves and also to untreated tobacco leaves to impart thereto desirable flavors.” Like Amster, Garner teaches that the extracted tobacco is still suitable use in smoking and other tobacco products (U.S. Pat. No. 2,128,043).
Despite this eighty year old work, Applicants are not aware that the teachings of Amster or Garner have been used in commercial processes or products.
Entering the present era, Keritsis et al (assigned to Philip Morris) (U.S. Pat. No. 4,936,920)(1990) mentions tobacco wax in a list of saccharides and polysaccharides that may be used as a bonding agent when making manufactured tobacco (more typically referred to as reconstituted tobacco sheet).
Renaud et al., in U.S. Pat. No. 8,863,754 (assigned to Philip Morris) (2014) describe compositions for heat not burn applications. The patent mentions tobacco wax in a reference to degradation products the presence of which evidences (unwanted) combustion: “Isoprene is a pyrolysis product of isoprenoid compounds present in tobacco, for example in certain tobacco waxes, and can be present in the aerosol only if the strands of homogenized tobacco material are heated to a temperature substantially higher than that required to generate an aerosol. Thus, isoprene yield can be taken as representative of the amount of homogenized tobacco material that is “over heated.”” Nothing in the disclosure indicates that tobacco wax has been purposefully used in this composition or otherwise present than through the natural presence of wax in the tobacco used to manufacture the “homogenized tobacco material.” Applicant understands the substrate described in this art to be a reconstituted tobacco sheet intended for use in heat not burn applications.
Brown et al. (assigned to Lorillard)(U.S. Pat. No. 9,038,644)(2015) teaches tobacco wax for use as a phase transition material to impart reduced ignition propensity to a cigarette. The wax is applied to the cigarette paper using high precision wax jet printing.
Each of U.S. Pat. Nos. 1,624,155; 2,128,043; 4,936,920; 4,936,920; 8,863,754; and 9,038,644, is expressly incorporated herein together with all citations in these references.
The vaporization of nicotine containing liquids is well known and popular, including using devices such as electronic cigarettes and tank-style (and non tank) personal vaporizers. Typically such compositions include USP (99.9% pure) nicotine oil as an ingredient, though zero-liquids without any nicotine are also used.
Heat not burn tobaccp systems are known in the tobacco industry. Heat not burn systems like Pax Lab's Pax® and Philip Morris' IQOS® (as well as earlier versions of IQOS® sold as Heatbar® and Accord®) heat tobacco compositions substantially without burning the tobacco, thereby aerosolizing volatile constituents of the tobacco composition. After use, the non-vaporized components of the tobacco composition remain minus those components what were successfully vaporized (or inadvertently burned).
In the case of both Pax® and IQOS® this residue is substantial and represents the substantial mass of the original tobacco composition.
Philip Morris International (PMI) describes the rationale behind heat not burn systems thusly: “[t]he concept behind ‘heat-not-burn’ is that heating tobacco, rather than burning it, reduces or eliminates the formation of many of the compounds that are produced at the high temperatures associated with combustion. Research has demonstrated that most of the harmful and potentially harmful constituents (HPHCs) in cigarette smoke are formed by thermal breakdown of the tobacco when it is burned. Heat-not-burn therefore offers the possibility of significantly reducing both the number and the levels of HPHCs generated by tobacco products, whilst retaining an acceptable sensory experience for current adult smokers” (from pmiscience.com).
Now, some criticism has been leveled against heat not burn systems, which ostensibly is premised on the notion that tobacco and heat will always tend lead to toxicant formation. Stephen Stotesbury, head of scientific and regulatory affairs for Imperial Tobacco has been quoted saying about Philip Morris International's IQOS [heat not burn] system: “There's a lot of black crud in the iQOS device after using it . . . . It smells like an ashtray.” Perhaps not surprisingly, Imperial Tobacco has stated it will not develop a heat not burn product—presumably to rely solely on its electronic nicotine delivery systems (ENDS).
Pax is a loose-leaf style vaporizer for use with “loose-leaf plant material” supplied by the user herself (-www.paxvapor.com/support/pax-2-faq/#can-i-use-liquids-in-pax-2). An earlier heat not burn composition—Pax Labs' Ploom® used a tobacco-humectant composition contained in a capsule of the style produced (filled with coffee) by NESCAFÉ®—however this product has been discontinued.
Philip Morris' IQOS is a more sophisticated product wherein the user uses a manufacturer-supplied “cigarette” in the heating device. The cigarette itself is comprised of reconstituted tobacco sheet made with high amounts of humectant (glycerin) that, together with other volatiles, create a vapor like experience when used.
Applicants believe the composition of the reconstituted sheet used in IQOS is akin to that described in WO2016050472A1, assigned to Philip Morris. One of the present inventors has extensive experience working with film and sheet systems, principally for pharmaceutical applications and is a named inventor on Fuisz et al. U.S. Pat. Nos. 9,108,340; 8,906,277; 8,685,437; 8,663,687; 8,652,378; 8,617,589; 8,613,285; 8,603,514; 8,241,661; 8,017,150; 7,972,618; 7,897,080; 7,824,588; 7,666,337; and 7,425,292.
Heat not burn systems does reduce HPHCs as stated by the PMIScience excerpt above. The toxicant profile of burning tobacco is well understood. Researchers have estimated that cigarette smoke contains 7,357 chemical compounds from many different classes (Warnatz, J, U Maas and R W Dibble. Combustion: physical and chemical fundamentals, modeling and simulation, experiments, pollutant formation. 2006). There is broad scientific agreement that several of the major classes of chemicals in the combustion emissions of burned tobacco are toxic and carcinogenic (Rodgman, A, and T A Perfetti. The chemical components of tobacco and tobacco smoke. 2013: CRC press).